How to write string program in java

Answer 1

https://www.sololearn.com/learn/Java/2142/?ref=app

Answer 2

C program to find frequency of characters in a string...
#include <stdio.h>
int main()
{
char str[1000], ch; int i, frequency = 0;
printf("Enter a string: ");
gets(str);
printf("Enter a character to find the frequency: ");
scanf("%c",&ch);
for(i = 0; str[i] != '\0'; ++i)
{
if(ch == str[i]) ++frequency;
}
printf("Frequency of %c = %d", ch, frequency); return 0;
}

source:
https://www.programiz.com/c-programming/examples/frequency-character